California Native Plant Society
San Gabriel Mountains Chapter

Events and news


Both members and visitors are welcome at our regular meetings, held at Eaton Canyon Nature Center beginning at 7:30 p.m. on the fourth Thursday of each month except July, August, November, and December. The meetings are preceded from 7:00 to 7:30 p.m. by social time and informal plant identification.

Thursday, March 22, 2018, 7:30 p.m.: Rare plants of the high San Gabriel Mountains: Oreonana vestita (woolly mountain parsley) and its associates, with Jane Tirrell: The woolly mountain parsley, Oreonana vestita (Apiaceae), California Native Plant Rank 1B.3, occurs primarily on ridges and summits that are intermittently covered with snow during the winter and spring. A study of this plant and its habitat may yield information on how plants adapt to climate change. O. vestita occurs over a wide elevation range, from 5,200 to 10,060 feet above sea level, and is associated with different plant communities according to the elevation. This talk will discuss O. vestita's natural history and phenology (the timing of events such as flowering and fruiting) and will showcase associated plants and trees across this elevation range with a focus on rare plants.

Jane Tirrell became interested in native plants when she retired in 2010 from Keck Graduate Institute (one of the Claremont Colleges), where she had been Associate Dean of Faculty. She joined the California Native Plant Society that same year and became a participant in our chapter's Lily Spring Area Survey. The Lily Spring Area Survey was a phenology study and plant species survey that compared observations made in 2010 to 2012 with those made in 1981. Her degrees are in biology and chemistry (BA Wellesley College) and biochemistry (PhD University of Massachusetts at Amherst). Her interest in Oreonana vestita and other plants at high elevation in the San Gabriel Mountains grew out of the Lily Spring Area Survey. Jane is our chapter's current treasurer.

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Thursday, April 26, 2018, 7:30 p.m.: Who knew? Floristic exploration of Griffith Park, the most driven-by park in the world, with Dan Cooper: Botanically, Griffith Park, at the far eastern edge of the Santa Monica Mountains, was fairly well collected during the 1900-1930 time period, with familiar names like Epling, Braunton, Davidson, and Detmers active in this era before the (human) population explosion of Los Angeles later in the century. With its rugged peaks and canyons discouraging all but the most adventurous selfie-seekers, the park provides a “living laboratory” on how our local flora has adapted to environmental change, including the survival of tenacious natives, and the invasion of even more successful non-native weeds. Ten years ago, Dan began active plant collection in the park, in an effort to completely (re-) document the existing flora – initially to follow the effects of a major wildfire in May 2007, and later, with the realization that someone needed to voucher its vanishing species before they were gone, the victims of weed-invasion, loss of pollinators, trampling, and other ills. Here he reviews the diversity of this “urban island”, focusing on some of the botanical surprises located among its 326 native species in the past decade. He also searches for patterns in the list of taxa believed extirpated from Griffith Park since 1960 (46 taxa), and discusses those that may soon join this list, known today from just one or two tiny populations here.

Daniel S. Cooper is a doctoral student in Ecology and Evolutionary Biology at UCLA and former California Director of Bird Conservation for the National Audubon Society. He has been collecting and analyzing ecological data, and communicating findings to resource managers and decision-makers for the past two decades. He has published more than two dozen peer-reviewed papers on California natural history, and is the author of Important Bird Areas of California (2004) and Flora of Griffith Park (2015). He is a San Gabriel Valley native and now lives in Ventura County near Thousand Oaks with his wife and two children.

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Thursday, May 24, 2018, 7:30 p.m.: Lessons learned from 12 years of local stewardship in an urban nature park in Southern California, with Barbara Eisenstein: Cities love to cut ribbons at park openings; however, it is what happens next that determines the success or failure of urban habitat parks. Without proper care, even beautifully designed and installed landscapes will fail. For twelve years volunteers have been caring for a nature park in the city of South Pasadena to prevent it from reverting to its formerly degraded state. Prior to the creation of the park, the site along the Arroyo Seco Flood Control Channel was used for illegal dumping, homeless encampments and passive recreation including walking and horseback riding. Within six months of the opening in 2004 the recently extirpated weeds were making an impressive comeback on the three-acre parcel. In response, Barbara initiated a volunteer park stewardship program, Friends of South Pasadena Nature Park. Over the years the group has developed strategies for replacing noxious weeds with locally appropriate native plants. Many of these practices would work in other newly designated urban habitat parks. Though it has taken years – and there is still much work to do – a small team of volunteers, with city support, is gradually improving conditions in the park.

Barbara Eisenstein is a native plant gardener, writer and blogger. Her book, “Wild Suburbia – Learning to Garden with Native Plants”, guides new and experienced gardeners on a journey toward sustainable, habitat gardening. Barbara is a research associate at Rancho Santa Ana Botanic Garden, Plant Sale Chair of the CNPS San Gabriel Mountains Chapter), and founder of Friends of South Pasadena Nature Park.

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Thursday, June 28, 2018, 7:30 p.m.: Talks by two of our award recipients: This month we have 20-minute talks from two CNPS San Gabriel Mountains Chapter award recipients. Sophie Winitsky is a second year Masters Student at Rancho Santa Ana Botanic garden and received a student research grant in 2016 from the CNPS San Gabriel Mountains Chapter.  She will be presenting an update on her research project. Dylan Cohen is a PhD student at Rancho Santa Ana Botanic Garden and was awarded a stipend to attend the CNPS Conservation Conference. Dylan's talk covers the research he presented at the conference.

A vascular flora of the Ad obe Valley and surrounding hills, Mono County, CA, with Sophia Winitsky: This study aims to document the vascular flora of the Adobe Valley and surrounding hills in Mono County, CA. Less than 100 herbarium specimens are recorded from the 90 square mile study area based on a search of the Consortium of California Herbaria, with little botanical documentation away from well-established roads or in the alkali meadows. At the center of the study area the U.S. Fish and Wildlife Service manages the River Spring Preserve, a 638-acre alkali and freshwater wetland. The preserve emphasizes the importance of the alkali flat ecosystem, a habitat that is representative of Owens Valley, but severely threatened by drought, trampling by cattle and feral horses, off-road vehicles, and water diversion. Alkaline ecosystems farther south have experienced more severe water pumping making the Adobe Valley a good place to establish baseline information to better understand sustainable groundwater extraction. In addition, there is a need for a floristic checklist of the River Spring Preserve as specified in the Preserve's 2016 Management Plan. Many endemic species have the potential to occur in the Adobe Valley and surrounding hills, so far Sophia has documented the following California Native Plant Society listed species: Allium atrorubens var. cristatum (Alliaceae), Calochortus excavatus (Liliaceae), Ivesia kingii var. kingii (Rosaceae), Cymopterus globosus (Apiaceae), Crepis runcinata subsp. hallii (Asteraceae), Plagiobothrys parishii (Boraginaceae), Spartina gracilis (Poaceae), and Sphaeromeria potentilloides var. nitrophila (Asteraceae), and Tetradymia tetrameres (Asteraceae). Her goal is to systematically document the vascular flora of the region, publish a voucher-based checklist, and increase the overall understanding of this severely threatened ecosystem.

Decrypting phylogenetic placement and specific level relationships from a recent radiation for the CNPS listed rare plant Mentzelia polita (Loasaceae), with Dylan Cohen: The Mentzelia section Bartonia (Loasaceae) is the result of a rapid recent radiation throughout the Intermountain Ranges and deserts of the western United States. Mentzelia polita is taxonomically placed within section Bartonia and is listed by CNPS as 1B.2, rare or endangered in California and elsewhere. The ‘subshrubby' Bartonia clade includes M. polita and occurs primarily within the Mojave Desert. Historically this group has been challenging, with distinctions between taxa subtle at best. Problematic species include M. polita, M. oreophila, and M. leucophylla. Menztelia polita and M. oreophila both occur in California and Nevada, while M. oreophila ranges more widely. Both of the former taxa have been suggested to differ morphologically between their CA and NV populations. Furthermore, M. leucophylla is a federally listed endemic only found in Ash Meadows, NV, but has been suggested to occur in habitats similar to Ash Meadows within boarder California. Geographically, Ash Meadows is less than ten miles from the boarder of CA. Mentzelia leucophylla also has been confused historically with M. oreophila. Restriction Site Associated DNA Sequencing (RAD-Seq) is used to elucidate relationships among members of the Mentzelia section Bartonia ‘subshrubby' clade. Further considerations are given towards a conservation plan for ‘M. polita' within California.

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Past programs of our chapter: See the Past Events page.

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For a schedule of state-wide events: California Native Plant Week

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Email notification: If you wish to be notified by email of upcoming field trips, please click here to subscribe to our email list.

Leaders: Each outing has one or more appointed leaders. It is not necessary to contact the leader beforehand in order to participate. All you need to do is turn up for the event.

Eaton Canyon Plant Walks

Plant walks are held on the second Sunday of each month except July and August.

Meet in front of Eaton Canyon Nature Center at 9:00 a.m. Then go on a leisurely walk, about 2 hours, through the native plant garden that surronds the Center and into the nearby wild areas. The walk is different each time — what's leafing out, flowering, in seed, etc., determines what your leade will talk about — and different leaders bring drifferent points of view.

Current plant walks: Sunday, November 12, 2017, 09:00

Sunday, December 10, 2017, 9:00

Sunday, January 14, 2018, 09:00

Sunday, February 11, 2018, 09:00

Sunday, March 11, 2018, 09:00

Sunday, April 8, 2018, 09:00

SUnday, May13, 2018, 09:00

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Field outings for 2018

We sponsor outings on occasional dates throughout the year, usually on a Saturday. The walking ranges from easy, typically on wide fire roads, to moderately strenuous, such as on forest trails. If a convenient place is available nearby, we love to picnic afterward. Weather is unpredictable; snow, rain, fire and ice cancel.

Important note: The chapter does not advertise all field trips in the newsletter. Instead we have two levels of field trip, those with dates known well ahead to places expected to be good regardless of the season; and spur-of-the-moment trips organized with 1 to 2 weeks of notice, based on seasonal conditions and notified via this web site, email, and Facebook. This gives us more flexibility in finding wildflowers in bloom or fall color at its peak.

Past outings/field trips of our chapter: See the Past Events page.

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Statewide and other CNPS chapter events

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Our chapter becomes involved in projects from time to time. Some recent projects include:

Lily Spring Area Survey: Click here for the Lily Spring Area Survey page.

The Paintbrush Quest: A survey of Castilleja gleasoni, our chapter logo. Click here for the Paintbrush Quest pages.

Millard Canyon Project — a fundraiser in support of Altadena Foothills Conservancy

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Next board meeting: See the Our Chapter page. Everyone is welcome.

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Our 2016 Plant Sale

Held in early November, the next sale is on November 5, 2016, at Eaton Canyon Nature Center. See the Plant sale page for details.

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February-July 2018, Saturday Strolls in the Nature Gardens, with Carol Bornstein: On the second Saturday of each month February through July 2018 from 9:30 to 11:00 a.m., join Carol Bornstein, director of the Natural History Museum's Nature Gardens, on a morning walk through the always-changing Nature Gardens. That's February 10, March 10, April 14, May 12, June 9, and July 14.

This will be especially helpful if you are needing to choose plants from the wide variety in local nurseries. Carol will discuss which plants are tough, which are fussy, how much to water, and what kind of plants attract butterflies, birds, and other wildlife to your home garden.

The cost is free with museum admission. The Natural History Museum is at 900 Exposition Blvd, Los Angeles, CA 90007. Meet at the North ticket booth. For further information call 213.763.3273 Click here for a flier.

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Volunteer opportunity: Sunland Welcome Nature Garden: The Sunland Welcome Nature Garden, a volunteer native plant garden on Sunland Boulevard at the 210 freeway, is a showcase of local native plants. Stop in and smell the flowers, visit the garden's Facebook page, or contact the garden's instigator Roger Klemm at for more information or to join in the next workday.

Southern California Botanists: See their Field Trips and events page (click here.)

Natural Sciences Section of Angeles Chapter of the Sierra Club, 2015 outings: For their current schedule, please see their web site (click here.)

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Click here for the past events page.

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